In recent years, memory systems comprising nonvolatile memories have become widespread.
As one of the above memory systems, a solid-state drive (SSD) based on NAND flash technology is known.
Recently, in the server of a data center, an SSD has been used as storage. In the server of the data center, access requests (read requests, write requests, etc.,) may be concurrently issued from a plurality of end users to the SSD.
In this case, if a read request is issued for a nonvolatile memory die in which a write operation is in progress (access contention), the response time to the read request (read latency) is very long. In this way, the I/O performance may be degraded.